Use of alkylpolyxylosides in cosmetics

ABSTRACT

The invention concerns the use of an alkylpolyxyloside obtained from a Guerbet alcohol having 16 to 28 carbon atoms as cosmetic feel-enhancing oil-in-water emulsions containing a polymer. The invention also concerns oil-in-water emulsions containing such an alkylpolyxyloside.

[0001] The subject of the present invention is the use of particular alkylpolyxylosides as agents enhancing the cosmetic feel of oil-in-water emulsions containing a polymer, and the oil-in-water emulsions containing such alkylpolyxylosides.

[0002] Cosmetic emulsions with an aqueous continuous phase (that is to say of the oil-in-water or O/W type) increasingly frequently contain polymers which are used as thickeners, emulsifiers or stabilizers. The use of these polymers makes it possible to reduce or eliminate the quantity of traditional emulsifiers. However, the feel of the cosmetic compositions thus obtained loses in richness and becomes aqueous.

[0003] Patent application FR 00 04414, filed on 6 Apr. 2000, describes compounds of formula:

R—O—(X)_(p)

[0004] in which:

[0005] p represents a decimal number between 1 and 5,

[0006] X represents a xylose residue, and

[0007] R represents a branched alkyl radical of formula:

CH(C_(n)H_(2n+1))(C_(m)H_(2m+1))—CH₂—

[0008] in which m is an integer between 6 and 18, n is an integer between 4 and 18 and the sum n+m is greater than or equal to 10.

[0009] These compounds are recommended as surfactants.

[0010] It has now been discovered that alkylpolyxylosides obtained from a Guerbet alcohol having from 16 to 28 carbon atoms make it possible to enhance the feel of oil-in-water emulsions containing a polymer.

[0011] Thus, according to a first aspect, the subject of the invention is the use of an alkylpolyxyloside of formula:

R—O—(X)_(p)  (I)

[0012] in which:

[0013] p represents a decimal number between 1 and 5,

[0014] X represents a xylose residue, and

[0015] R represents a branched alkyl radical of formula:

CH(C_(n)H₂₊₁)(C_(m)H_(2m+1))—CH₂—

[0016] in which m is an integer between 6 and 12, n is an integer between 8 and 16 and the sum n+m is in the range from 14 to 26;

[0017] or alternatively of a composition consisting of a mixture of at least two alkylpolyxylosides as defined above;

[0018] as agent enhancing the cosmetic feel of water-in-oil emulsions containing one or more polymers.

[0019] Preferably, the sum n+m is equal to 14, 16, 18, 22 or 26 and R represents more particularly a 2-hexyldecyl (m=6, n=8), 2-octyldecyl (m=8, n=8), 2-hexyldodecyl (m=6, n=10), 2-octyldodecyl (m=8, n=10), 2-decyltetradecyl (m=10, n=12) or 2-dodecylhexadecyl (m=12, n=14) radical. In a particularly preferred manner, the sum m+n is greater than 16, and is advantageously equal to 18, 22 or 26, more preferably still equal to 22 or 26.

[0020] In formula R-O—(X)_(p), the group R—O— is linked to X by the anomeric carbon of the xylose residue, so as to form an acetal functional group.

[0021] p, which represents the average degree of polymerization of the xylose, is more particularly between 1 and 2.5, and most particularly between 1 and 2.0.

[0022] The compound of formula R—O—(X)_(p) may be prepared by reacting xylose with an excess of a fatty alcohol of formula ROH, and then removing the unreacted fatty alcohol.

[0023] In the process as defined above, the reaction is carried out in the presence of strong acid catalysts.

[0024] According to one variant of the process as defined above, the xylose is reacted with an alcohol of formula R₁—OH, in which R₁ contains from 1 to 4 carbon atoms and more particularly with butanol, to give the acetal of formula R₁O—(X)_(p), which then undergoes transacetalization with an excess of alcohol of formula ROH with distillation of the alcohol of formula R₁OH formed and then removal of the unreacted alcohol of formula ROH.

[0025] In this process and its variant, as described above, the removal of the unreacted alcohol of formula ROH is carried out according to methods known to persons skilled in the art such as for example distillation, thin-film distillation, molecular distillation or solvent extraction.

[0026] According to a second aspect, the subject of the present invention is an oil-in-water emulsion comprising:

[0027] from 0.1 to 15% by weight of one or more alkylpolyxylosides as defined above;

[0028] from 0.05 to 10% by weight of one or more polymers;

[0029] more than 5% by weight, preferably more than 7% by weight, and more preferably still more than 10% by weight, and up to 50% by weight of a fatty phase consisting of one or more oils and/or one or more waxes.

[0030] According to an advantageous embodiment, the alkylpolyxyloside of formula (I) is in the form of a mixture with its corresponding Guerbet alcohol (of formula ROH where R has the meaning given above), in an alkylpolyxyloside/alcohol weight ratio in the range from 1/99 to 99/1.

[0031] Among the polymers used in the oil-in-water emulsion according to the present invention, there may be mentioned in particular homopolymers or copolymers of acrylic acid, acrylic acid derivatives, acrylamide and its derivatives, acrylamidomethylpropanesulfonic acid, vinyl monomer, trimethylaminoethylacrylate chloride such as for example the products marketed under the name CARBOPOL® Ultrez 10, PEMULEN® TR1 and TR2, SIMULGEL®A, SIMULGEL®NS, SIMULGEL®EPG, SIMULGEL®EG, LUVIGEL®EM, SALCARE®SC91, SALCARE®SC92, SALCARE®SC95, SALCARE®SC96, FLOCARE®ET100, HISPAGEL®, SEPIGEL®305, SEPIGEL®501, SEPIGEL®502, FLOCARE®ET58, STABILEZE®06; hydrocolloids of plant or biosynthetic origin such as for example xanthan gum, karaya gum, carrageenans, alginates; silicates, cellulose and its derivatives; starch and its hydrophilic derivatives; polyurethanes.

[0032] Among the oils which can be used in the context of the present invention, there may be mentioned in particular:

[0033] oils of plant origin, such as sweet almond oil, copra oil, castor oil, jojoba oil, olive oil, rapeseed oil, peanut oil, sunflower oil, wheatgerm oil, corn germ oil, soybean oil, cottonseed oil, alfalfa oil, poppy seed oil, pumpkinseed oil, evening primrose oil, millet oil, barley oil, rye oil, safflower oil, candlenut oil, passion flower oil, hazelnut oil, palm oil, shea butter, apricot kernel oil, calophyllum oil, sisymbrium oil, avocado oil, calendula oil;

[0034] vegetable oils and their ethoxylated methyl esters;

[0035] oils of animal origin, such as squalene, squalane;

[0036] mineral oils such as paraffin oil, liquid paraffin and isoparaffins;

[0037] synthetic oils, in particular fatty acid esters such as butyl myristate, propyl myristate, cetyl myristate, isopropyl palmitate, butyl stearate, hexadecyl stearate, isopropyl stearate, octyl stearate, isocetyl stearate, dodecyl oleate, hexyl laurate, propylene glycol dicaprylate, esters derived from lanolic acid, such as isopropyl lanolate, isocetyl lanolate, monoglycerides, diglycerides and triglycerides of fatty acids, such as glyceryl triheptanoate, alkyl benzoates, poly-alpha-olefins, polyolefins such as polyisobutene, synthetic isoalkanes such as isohexadecane, isododecane, perfluorinated oils and silicone oils.

[0038] Among the waxes which can be used in the context of the present invention, there may be mentioned for example beeswax; carnauba wax; candelilla wax; ouricoury wax; Japan wax; cork fiber or sugarcane wax; paraffin waxes; lignite waxes; microcrystalline waxes; lanolin wax; ozokerite; polyethylene wax; hydrogenated oils; silicone waxes; vegetable waxes; fatty alcohols and fatty acids which are solid at room temperature; glycerides which are solid at room temperature.

[0039] The water-in-oil emulsion in accordance with the present invention may also optionally contain up to 15% by weight of an emulsifier.

[0040] Among the emulsifiers which can be used in the context of the present invention, there may be mentioned for example fatty acids; ethoxylated fatty acids; fatty acid esters of sorbitol; ethoxylated fatty acid esters; polysorbates; polyglycerol esters; ethoxylated fatty alcohols; sucrose esters; alkylpolyglycosides; sulfated and phosphated fatty alcohols.

[0041] In a manner known per se, these emulsions may additionally comprise one or more compounds chosen from humectants, such as for example glycerin, preservatives, colorants, perfumes, cosmetic active agents, inorganic or organic sunscreens, inorganic fillers such as iron oxides, titanium oxides and talc, synthetic fillers such as nylons and polymethyl methacrylates which are crosslinked or not, silicone elastomers, sericites and plant extracts.

[0042] The oil-in-water emulsions in accordance with the invention may be prepared in the following manner.

[0043] The aqueous phase is heated to a temperature of 70 to 85° C. In parallel, the fatty phase containing the emusifying system of the invention and the oils (optionally additivated with waxes, coemulsifiers and lipophilic active agents) is heated to an identical temperature of 70 to 85° C. The two phases are then mixed and emulsified with the aid of a rotor-stator type emulsifier (for example a SILVERSON laboratory mixer). After a few minutes of emulsification, the emulsion is cooled with gentle stirring. The polymer(s) are introduced into the oily phase, into the aqueous phase or directly into the emulsion according to the recommendations of the suppliers.

[0044] If all the components of the emulsion are liquid, the manufacture may be carried out without heating.

[0045] The invention will be illustrated with the following examples.

EXAMPLE 1 Preparation of a 2-decyltetradecylxyloside

[0046] 61.8 kg of 2-decyltetradecanol, marketed by the company SASOL under the name Isofol®24, are introduced into a reactor. 8.7 kg of xylose are gradually dispersed in the stirred medium and 65 g of sulfuric acid are then added. The mixture is kept at 115° C. for 6 hours, under a partial vacuum, and then neutralized with caustic soda. After filtration, the clear liquid obtained has a hydroxyl value of 183 and contains 15% by weight of 2-decyltetradecylxyloside and 85% by weight of 2-decyltetradecanol.

EXAMPLE 2 Demonstration of the Feel Enhancement Obtained when the Compound According to Example 1 is Added to Cosmetic Preparations Containing no Emulsifier

[0047] Two series of emulsions having the following compositions are prepared: 1st series Cetearyl octanoate 10% Water qsp 100% Polymer qs Preservatives qs 2nd series Compound according to example 1  3% Cetearyl octanoate 10% Water qsp 100% Polymer qs Preservatives qs

[0048] Mode of preparation: the polymer is dispersed in water and neutralized if necessary, and then cetearyl octanoate is introduced into the gel formed. Homogenization of the emulsion is carried out without heating, by stirring with traditional items of equipment. The compound according to example 1 is added with cetearyl octanoate.

[0049] The preparations obtained are O/W emulsions.

[0050] A sensory evaluation is carried out on a panel of 20 trained volunteers. The results are presented in table 1. Each criterion is scored from 0 to 5. TABLE 1 Carbomer 0.4% Polyacrylamide and and acrylates/ C11-13 steareth-20 Acryloyl isoparaffin methacrylate dimethyl and laureth-7: copolymer taurate Polymer 3% 0.2% copolymer 1% Evaluation of the emulsions without the compound according to example 1 Richness 2 0 0 Residual film 2 1 1 Evaluation of the emulsions containing 3% of the compound according to example 1 Richness 3 2 3 Residual film 4 3 3

[0051] The addition of 3% of the compound according to example 1 to the polymer-based emulsions significantly enhances the richness and increases the sensation of emollience, leaving a residual film significantly perceived by the volunteers.

EXAMPLE 3 Demonstration of the Feel Enhancement Obtained when the Compound According to Example 1 is Added to Cosmetic Preparations Containing an Emulsifier

[0052] Two emulsions having the following composition are prepared: Emulsifier   3%   3% Compound according to example 1   3% Cetearyl octanoate  10%  10% Water qs 100% qs 100% Polyacrylamide and C11-13 1.5% 1.5% isoparaffin and laureth-7 Preservatives qs qs

[0053] The preparation of these emulsions is carried out according to a conventional process by emulsification in the hot state of 2 aqueous and oily phases.

[0054] The preparations obtained are O/W emulsions.

[0055] A sensory evaluation is carried out on a panel of 20 trained volunteers. The results are presented in table 2. Each criterion is scored from 0 to 5. TABLE 2 Arachidyl alcohol and behenyl PEG 100 alcohol and stearate and arachidyl glyceryl Ceteth 2 + ceteth Emulsifier glucoside stearate 21 Evaluation of the trials without the compound according to example 1 Richness 1 1 0 Residual film 1 1 1 Evaluation of the trials containing 3% of the compound according to example 1 Richness 3 2 2 Residual film 3 3 3

[0056] The addition of 3% of the compound according to example 1 makes it possible to significantly enhance the sensory profile of the emulsions tested by simultaneously increasing the richness and the residual film. 

1-10. (canceled).
 11. A composition to enhance the cosmetic feel of oil-in-water emulsions comprising at least one alkylpolyxyloside represented by formula (I): R—O—(X)_(p)  (I), wherein said p is the average degree of polymerization, and is a decimal number in the range of from about 1 to about 5, wherein said X is a xylose residue, and wherein said R is a branched alkyl radical represented by the formula: CH(C_(n)H_(2n+1))(C_(m)H_(2m+1))—CH₂—; wherein said m is an integer in the range of from about 6 to about 12, wherein said n is an integer in the range of from about 8 to about 16, and wherein the sum m+n is in the range of from about 14 to about
 26. 12. The composition according to claim 11, wherein said composition further comprises at least one polymer selected from the group consisting of: a) polymers of acrylic acid, b) acrylic acid derivatives, c) acrylamide and its derivatives, d) acrylamidomethylpropanesulfonic acid, e) vinyl monomer, and f) trimethylaminoethylacrylate chloride.
 13. The composition according to claim 11, wherein said p is in the range of from about 1 to about 2.5.
 14. The composition according to claim 13, wherein said range is from about 1 to about
 2. 15. The composition according to claim 11, wherein the sum m+n is equal to at least one integer selected from the group consisting of: a) 14, b) 16, c) 18, d) 22, and e)
 26. 16. The composition according to claim 15, wherein said sum is greater than about
 16. 17. The composition according to claim 15, wherein said sum is equal to about
 18. 18. The composition according to claim 15, wherein said sum is equal to about
 22. 19. The composition according to claim 15, wherein said sum is equal to about
 26. 20. The composition according to claim 11, wherein said R is at least one component selected from the group consisting of: a) 2-hexyldecyl, b) 2-octyldecyl, c) 2-hexyldodecyl, d) 2-octyldodecyl, e) 2-decyltetradecyl, and f) 2-dodecylhexadecyl radical.
 21. An oil-in-water emulsion composition comprising from about 0.1 to about 15% by weight of at least one alkylpolyxyloside represented by formula (I): R—O—(X)_(p)  (I), wherein said p is a decimal number in the range of from about 1 to about 5, wherein said X is a xylose residue, and wherein said R is a branched alkyl radical represented by formula (II): CH(C_(n)H_(2n+1))(C_(m)H_(2m+1))—CH₂—  (II) wherein said m is an integer in the range of from about 6 to about 12, wherein said n is an integer in the range of from about 8 to about 16, and wherein the sum of n+m is in the range of from about 14 to about
 26. 22. The composition according to claim 21, wherein said composition further comprises from about 0.05 to about 10% by weight of at least one polymer.
 23. The composition according to claim 21, wherein said composition further comprises from about 5% to about 50% by weight of a fatty phase.
 24. The composition according to claim 23, wherein said fatty phase further comprises at least one component selected from the group consisting of: a) oils; and b) waxes.
 25. The composition according to claim 22, wherein said polymer comprises at least one component selected from the group consisting of: a) polymers of acrylic acid, b) acrylic acid derivatives, c) acrylamide and its derivatives, d) acrylamidomethylpropanesulfonic acid, e) vinyl monomer, and f) trimethylaminoethylacrylate chloride.
 26. The composition according to claim 24, wherein said oil is selected from the group consisting of: a) oils of plant origin, b) sweet almond oil, c) copra oil, d) castor oil, e) jojoba oil, f) olive oil, g) rapeseed oil, h) peanut oil, i) sunflower oil, j) wheatgerm oil, k) corn germ oil, l) soybean oil, m) cottonseed oil, n) alfalfa oil, o) poppy seed oil, p) pumpkinseed oil, q) evening primrose oil, r) millet oil, s) barley oil, t) rye oil, u) safflower oil, v) candlenut oil, w) passion flower oil, x) hazelnut oil, y) palm oil, z) shea butter, aa) apricot kernel oil, bb) calophyllum oil, cc) sisymbrium oil, dd) avocado oil, ee) calendula oil; ff) vegetable oils and their ethoxylated methyl esters, gg) oils of animal origin, such as squalene, hh) mineral oils, ii) paraffin oil, jj) liquid paraffin, kk) isoparaffins; ll) synthetic oils, mm) fatty acid esters, nn) butyl myristate, oo) propyl myristate, pp) cetyl myristate, qq) isopropyl palmitate, rr) butyl stearate, ss) hexadecyl stearate, tt) isopropyl stearate, uu) octyl stearate, vv) isocetyl stearate, ww) dodecyl oleate, xx) hexyl laurate, yy) propylene glycol dicaprylate, zz) esters derived from lanolic acid, aaa) isopropyl lanolate, bbb) isocetyl lanolate, ccc) monoglycerides, ddd) diglycerides, eee) triglycerides of fatty acids, fff) glyceryl triheptanoate, ggg) alkyl benzoates, hhh) poly-alpha-olefins, iii) polyolefins, jjj) polyisobutene, kkk) synthetic isoalkanes, lll) isohexadecane, mmm) isododecane, nnn) perfluorinated oils, and ooo) silicone oils.
 27. The composition according to claim 24, wherein said wax comprises at least one component selected from the group consisting of: a) beeswax, b) carnauba wax, c) candelilla wax, d) ouricoury wax, e) Japan wax, f) cork fiber, g) sugarcane wax, h) paraffin waxes, i) lignite waxes, m) microcrystalline waxes, n) lanolin wax, o) ozokerite, p) polyethylene wax, q) hydrogenated oils, r) silicone waxes, s) vegetable waxes, t) fatty alcohols, u) fatty acids, and v) glycerides.
 28. The composition according to claim 21, wherein said alkylpolyxyloside is in the form of a mixture with its corresponding alcohol of formula ROH.
 29. The composition according to claim 28, wherein the weight ratio of alkylpolyxyloside/alcohol is in the range of from about 1/99 to about 99/1.
 30. The composition according to claim 21, wherein said composition further comprises up to about 15% by weight of an emulsifier.
 31. The composition according to claim 30, wherein said emulsifier is at least one component selected from the group consisting of: a) fatty acids, b) ethoxylated fatty acids, c) fatty acid esters of sorbitol, d) ethoxylated fatty acid esters, e) polysorbates, f) polyglycerol esters, g) ethoxylated fatty alcohols, h) sucrose esters, i) alkylpolyglycosides, j) sulfated and phosphated fatty alcohols, k) humectants, l) glycerin, m) preservatives, n) colorants, o) perfumes, p) cosmetic active agents, q) inorganic or organic sunscreens, r) inorganic fillers, s) iron oxides, t) titanium oxides, u) talc, v) synthetic fillers, w) nylons, x) polymethyl methacrylates which are crosslinked or not, y) silicone elastomers, z) sericites, and aa) plant extracts.
 32. The composition according to claim 21, wherein the sum of m+n is equal to about at least one integer selected from the group consisting of: a) 14, b) 16, c) 18, d) 22, and e)
 26. 33. The composition according to claim 32, wherein said integer is greater than about
 16. 34. The composition according to claim 32, wherein said integer is greater or equal to about
 22. 35. The composition according to claim 32, wherein said integer is greater than or equal to about
 26. 36. The composition according to claim 21, wherein said R is at least one component selected from the group consisting of: a) 2-hexyldecyl, b) 2-octyldecyl, c) 2-hexyldodecyl, d) 2-octyldodecyl, e) 2-decyltetradecyl, and f) 2-dodecylhexadecyl.
 37. A method to prepare an alkylpolyxyloside represented by formula (I): R—O—(X)_(p)  (I), wherein said p is a decimal number in the range of from about 1 to about 5, wherein said X is a xylose residue, and wherein said R is a branched alkyl radical represented by formula (II): CH(C_(n)H_(2n+1))(C_(m)H_(2m+1))—CH₂—  (II) wherein said m is an integer in the range of from about 6 to about 12, said n is an integer in the range of from about 8 to about 16, and the sum of n+m is in the range of from about 14 to about 26, comprising the steps of: a) introducing xylose to an excess of fatty alcohol of the form ROH, b) reacting said xylose with said excess of fatty alcohol, wherein the reaction is carried out in the presence of a strong acid catalyst, and c) removing the unreacted fatty alcohol from the reaction mixture, and d) collecting the alklpolyxyloside product. 